Taubira’s tweet came as riots erupted in the suburb of Ferguson outside St Louis after a grand jury chose not to press charges against a white officer who shot dead black teen Michael Brown in what he said was self-defence.

Martin was killed in 2012 by a neighbourhood watch volunteer during what he described as an altercation at night in the street.

Taubira later explained to France Info radio that she had wanted to express solidarity “in an extremely painful situation.”

“I am not making a value judgment on United States institutions (but) when the feeling of frustration is so strong, so deep, so lasting and massive, you have to ask yourself about the trust in these institutions,” said the minister.

“One realises this only happens to the same people, African American kids. So there is the problem of a certain number of cliches, portrayals, prejudices which can create terrible reflexes.”